How Altitude Affects Calories Burned During Hiking
Learn how high altitude increases calorie burn during hiking. Understand the science behind altitude-related energy expenditure.
Hiking at high altitude burns 10 to 30 percent more calories than at sea level due to reduced oxygen, increased breathing effort, and metabolic adaptation.
Understanding altitude's impact on energy expenditure is crucial for planning high-altitude adventures and ensuring adequate nutrition.
Altitude Calorie Multiplier Chart
| Altitude | Oxygen Level | Calorie Increase |
|---|---|---|
| Sea level | 100% | Baseline |
| 1,500m (5,000 ft) | 84% | +5-10% |
| 2,500m (8,200 ft) | 74% | +10-20% |
| 3,500m (11,500 ft) | 65% | +20-30% |
| 4,500m (14,800 ft) | 57% | +30-50% |
| 5,500m (18,000 ft) | 50% | +50-75% |
For base calculations, use our Hiking Calorie Calculator.
Why Altitude Increases Calorie Burn
1. Reduced Oxygen Availability
At altitude, air pressure drops and less oxygen is available per breath:
- Body compensates by breathing faster
- Heart rate increases
- More energy spent on basic respiration
Breathing effort increase:
- 1,500m: +10% breathing work
- 2,500m: +20% breathing work
- 3,500m: +35% breathing work
2. Increased Basal Metabolic Rate
The body's resting metabolism increases at altitude:
- Maintaining core temperature is harder
- Tissue oxygenation requires more work
- Sleep quality decreases, increasing fatigue
BMR increase by altitude:
| Altitude | BMR Increase |
|---|---|
| 2,000m | +3-5% |
| 3,000m | +7-10% |
| 4,000m | +10-15% |
| 5,000m | +15-20% |
3. Cold Temperature Effects
Higher altitude generally means colder temperatures:
- Body burns calories to maintain warmth
- Shivering can burn 200-400 kcal/hour
- Cold air requires warming in lungs
Temperature effect:
- 0°C to -10°C: +5-10% calories
- -10°C to -20°C: +10-20% calories
- Below -20°C: +20-40% calories
4. Increased Exercise Intensity
The same walking pace feels harder at altitude:
- Perceived exertion increases
- More rest breaks needed
- Heart rate elevated for same effort
Calorie Burn by Altitude Level
Moderate Altitude (1,500-2,500m / 5,000-8,200 ft)
| Activity | Sea Level | At Altitude | Increase |
|---|---|---|---|
| Easy hike | 300 kcal/hr | 330 kcal/hr | +10% |
| Moderate hike | 400 kcal/hr | 450 kcal/hr | +12% |
| Hard hike | 550 kcal/hr | 630 kcal/hr | +15% |
Examples: Colorado 14ers base, European Alps valleys
High Altitude (2,500-4,000m / 8,200-13,100 ft)
| Activity | Sea Level | At Altitude | Increase |
|---|---|---|---|
| Easy hike | 300 kcal/hr | 360 kcal/hr | +20% |
| Moderate hike | 400 kcal/hr | 500 kcal/hr | +25% |
| Hard hike | 550 kcal/hr | 715 kcal/hr | +30% |
Examples: Colorado summit zones, Mont Blanc, Kilimanjaro base
Very High Altitude (4,000-5,500m / 13,100-18,000 ft)
| Activity | Sea Level | At Altitude | Increase |
|---|---|---|---|
| Easy hike | 300 kcal/hr | 420 kcal/hr | +40% |
| Moderate hike | 400 kcal/hr | 580 kcal/hr | +45% |
| Hard hike | 550 kcal/hr | 850 kcal/hr | +55% |
Examples: Kilimanjaro summit, Everest Base Camp, Andes peaks
Extreme Altitude (5,500m+ / 18,000+ ft)
| Activity | Sea Level | At Altitude | Increase |
|---|---|---|---|
| Walking | 300 kcal/hr | 480 kcal/hr | +60% |
| Climbing | 450 kcal/hr | 765 kcal/hr | +70% |
Examples: High Himalayan climbs, extreme mountaineering
Acclimatization Effect
Calorie burn changes as you acclimatize:
Day 1-3 (Acute Phase)
- Maximum calorie increase
- Highest perceived effort
- Poor sleep = additional burn
Day 4-7 (Adaptation Phase)
- Calorie burn begins to normalize
- Body produces more red blood cells
- Efficiency improves
Day 8+ (Acclimatized)
- Calorie burn stabilizes at +10-20% above baseline
- Still elevated but manageable
- Performance improves
Nutrition Implications
Increased Calorie Needs
| Altitude | Daily Calorie Increase |
|---|---|
| 2,500m | +300-500 kcal |
| 3,500m | +500-800 kcal |
| 4,500m | +800-1,200 kcal |
| 5,500m | +1,200-1,800 kcal |
Food Planning for Altitude
Key principles:
- Increase carbohydrates: Easy to digest, quick energy
- Reduce fat intake initially: Harder to digest at altitude
- Eat frequently: Small meals every 2-3 hours
- Stay hydrated: Dehydration worsens altitude effects
Sample high-altitude menu:
- Breakfast: 700-900 kcal
- Morning snacks: 400-600 kcal
- Lunch: 500-700 kcal
- Afternoon snacks: 400-600 kcal
- Dinner: 800-1,000 kcal
- Evening: 200-400 kcal
Appetite Suppression
Paradoxically, appetite often decreases at altitude:
- Force yourself to eat
- Choose calorie-dense foods
- Drink calories when eating is difficult
Practical Recommendations
Before Your Trip
- Train at lower elevations first
- Build aerobic base
- Practice eating while exercising
During Altitude Hiking
- Start slow (50% normal pace)
- Eat before feeling hungry
- Drink before feeling thirsty
- Monitor for altitude sickness
Recovery
- Expect increased appetite when descending
- Rest days need fuel too
- Sleep more if possible
Calculate Your Altitude Burn
Use these calculators as a baseline, then add altitude factors:
Tip: Calculate base burn, then multiply by altitude factor (1.1-1.5).